The present invention relates to the field of containers for carrying objects, generally, and specifically to closable bags, or sacks, that people may use to carry a multiplicity of objects. More specifically, articles according to the present disclosure are related to the field of backpacks of the type used for carrying clothing, books, tools, food, and personal items. A preferred embodiment of the present disclosure is related more particularly to the field of convertible backpacks that can be carried comfortably on both of, or either one of, a person""s shoulders and which have one or more removeable, re-positionable straps that may be readily configured to accommodate the changing needs and preferences of each person who uses the backpack. For the purposes of the present disclosure, backpack, bookbag, knapsack, haversack, and rucksack, are deemed synonymous unless the context clearly distinguishes the meaning of one or more of those terms.
The popularity of backpacks has surged in recent years. With increased backpack use, there has been a corresponding increase in reports of injuries, especially among students, that result from carrying backpacks that are too heavy, from failing to maintain correct posture, and from carrying unbalanced loads. An estimated 3,300 children aged 5 to 14 were treated in emergency rooms in 1997 for injuries related to bookbags. Another study recently found that 6 percent of 10-year-olds complained of back pain, while 10 to 15 percent of 12-year-olds reportedly had back pain. Doctors believe one reason for the rising incidence of back pain among youth may be the modern-day bookbagxe2x80x94the backpack.
It is generally recommended that a loaded backpack should not exceed 10% of the weight of a child, and that the backpack should be carried on both shoulders. Health care professionals have consistently advised students and youths to carry backpacks over both shoulders. Despite these admonitions, many fashion-conscious students prefer to carry their packs by one strap over one shoulder, and if they do, they should alternate shoulders.
Backpacks of the type used by students are not merely utilitarian containers for objects that the wearer may need during the course of a day. They are also accessory articles of apparel that may be selected on the bases of color, pattern, style, brand name, or coordination with other articles of apparel. In addition to the utility and appearance of a backpack, the style and manner with which it is worn or carried is presently important to many students.
The risk of improper lifting and carrying is widely recognized in workplace settings. In the U.S. however, schools and other institutions with a constituency of children have not recognized any duty to reduce the exposure of their constituents to the risks of skeletal damage by discouraging their constituents from carrying backpacks that are too heavy. Other countries have observed the problem of students carrying backpacks that are too heavy. In 1996, the Bangkok, Thailand education ministry, concerned about the risk of spinal damage, set a backpack weight limit of six pounds for primary school students. Prior to banning heavier backpacks, the Bangkok education ministry had found that the weight of more than half the primary students"" backpacks exceeded six pounds.
Numerous examples of backpacks and similar gear have been designed with the purpose of reducing the strain to which the person using the gear is exposed. Development of backpacks generally has focused on enabling individuals to more easily carry items to which they wish to have ready access. Some pack apparatus are designed to hold the load closer to the body of the person carrying the pack. Maintaining the load close to a person""s body reduces the effort required to keep balance and reduces the leverage by which the burden can act against the person""s muscles.
Other designs seek to reduce the strain on the user by making it convenient to vary the way the pack is carried so that the exertion required to carry the load can be shifted among different muscle groups and, as a consequence, the other muscle groups can periodically rest and recover from exertion. Several inventors have developed bags that may be carried either on the back or under an arm by shoulder straps or else by grippable handles.
For example, U.S. Pat. No. 5,577,652 issued Nov. 26, 1996 to Cooper for a Convertible Backpack. Cooper""s patent is directed to a backpack that is convertible from one carrying method to another. The Cooper backpack can be carried with two shoulders, one shoulder, or with the strap crossing the wearer""s chest diagonally. The article differs from a conventional backpack in that a single strap is provided. Each end of the strap is fitted with a clasp that can engage the usual lower strap D-rings. Conventional backpacks normally have the upper end of each strap fixedly sewn to the center upper portion of the backpack. Cooper""s backpack is fitted with a ring, sleeve, slot, or loop through which the central part of the strap may slide. With equal parts of the strap on either side of the strap ring, the strap can fit onto both shoulders. The article may be converted to a shoulder bag, or tote, by sliding the strap to one side or the other and carrying the bag on only one shoulder. Cooper illustrates no provision for securing the carrying strap at any specific position. Neither this ""652 patent nor the Norton U.S. Pat. No. 4,810,102 has been designed to ameliorate the health risk issues that initiated development of embodiments according to the present disclosure.
U.S. Pat. No. 5,544,792 issued Aug. 13, 1996, to Arnwine for a Convertible Student Book Bag. Arnwine discloses a modular student book bag that is fitted at one location on the bag structure with a strap for carrying the bag with one shoulder and, at another location on the structure, a pair of straps for carrying the article with two shoulders. The straps appear to be neither re-locatable nor removable.
U.S. Pat. No. 5,209,384 issued May 11, 1993 to Anderson for a Portable Tool Kit. Anderson""s portable tool kit shows a bag that may be carried by a pair of shoulder straps. A pair of additional handles may be drawn to show carrying the kit with one hand or one shoulder.
U.S. Pat. No. 5,114,059 issued May 19, 1992 to Thatcher for a Universally Adjustable Frameless Backpack. The patent for Thatcher""s universally adjustable frameless backpack discloses a pack designed to meet different needs than those for which the present invention is intended. It does, however, show some construction techniques that may be adaptable for use in various models of the present invention.
U.S. Pat. No. 4,810,102 issued Mar. 7, 1989 to Norton for a Universal Sport Bag. Norton describes a sport bag that, although it is not explicitly designed as a backpack, does accommodate being carried on one shoulder, on two shoulders, or on a belt that encircles a person""s waist. Norton does not, however, disclose any enhancement that improves the ability of an individual to carry a backpack on one shoulder.
U.S. Pat. No. 4,660,751 issued Apr. 28, 1987 to von Dewitz for a Device to Secure Shoulder Straps of a Rucksack. Von Dewitz discloses a securement for the upper ends of shoulder straps for a backpack (or rucksack). The angles at which the straps attach to the pack can be varied to accommodate the build of the person who carries the pack.
U.S. Pat. No. 4,491,258 issued Jan. 1, 1985 to Jones for a Convertible Backpack. Jones discloses a good example of a backpack that may be converted into one or more other useful objects. The Jones disclosure was directed primarily toward mounting bags and panniers on bicycles that, when removed from a vehicle, could be configured so that a person could carry the bags as a backpack.
U.S. Pat. No. 2,422,218 issued Jun. 17, 1947 to Bauer for a Golf Club Bag. Bauer describes a golf club bag that has both hand and shoulder straps. The single shoulder strap is configured to enable the user to carry the bag with only one strap but also have the load be properly balanced. In fact Bauer states that his golf club bag provides xe2x80x9can improved form of a strap for shoulder carriage of the bag [the strap being] adapted to girdle the shoulder and arm pit for sustaining the bag in perpendicular slanting position for a self-balancing carriage.xe2x80x9d Bauer states that his carrier arrangement will xe2x80x9cavoid instituting a forearm downward pressure upon the bag and clubsxe2x80x9d to provide adequate balance and clearance. Bauer does not, however, disclose an apparatus that is compatible with the structure of a soft backpack or that is compatible with all of the various utilitarian and stylistic purposes to which backpacks are presently applied.
U.S. Pat. No. 2,224,568 issued Dec. 10, 1940 to Altorfer for a Ski Bag. Altorfer discloses a ski bag and ski attachment bracket that includes a sling, or harness, assembly that may be worn over one shoulder, both shoulders, or across the chest, depending on the preferences and the activities of the wearer.
U.S. Pat. No. 1,696,191 issued Dec. 25, 1928 to Coulson for a Pack. Coulson discloses a type of pack sling that is adjustable so that a suitcase can be carried on the shoulders and back of an individual traveler. The suitcase was asserted to be superior to soft packs for carrying articles.
U.S. Pat. No. 995,963 issued Jun. 20, 1911 to Harriman for a Pack Sling. Harriman discloses a pack sling that has adjustable shoulder straps and which is readily adapted to carrying a variety of other items.
U.S. Pat. No. 946,856 issued Jan. 10, 1910 to Harriman for a Combined Roll Carrier and Haversack. Harriman discloses a combined roll carrier and haversack that includes adjustable shoulder straps.
Despite the efforts of the workers mentioned previously and the efforts of many other inventors, artisans, and designers, there has not been a satisfactory product that is useful either for load-carrying purposes, generally, or for the purpose of meeting the needs of persons who use backpacks. Although numerous periodicals have published articles urging backpack users to carry their packs on both shoulders, many students routinely carry their backpacks slung over one shoulder. There may be several reasons that people choose to do so. Some people find it difficult or annoying to don and doff a backpack on both shoulders, especially if heavy coats are also being worn. It is likely that some people find that they can more quickly move from place to place and between classrooms if they do not take the time to put a backpack on both shoulders. Some people may find it more fashionable to carry a backpack by a single strap.
A backpack is a fashion accouterment that may be selected and worn for the purpose of satisfying many needs in beyond functioning to replace briefcases and bookbags. The way in which the backpack is worn (e.g. high, between the shoulder blades; low, at the small of the back, etc.) can serve as an identifiable link to a particular group. Members of particular groups may anticipate that others with similar taste in backpack fashion will share a cluster of beliefs, attitudes, and desires.
Other groups, such as the students enrolled at a particular college or university, may desire to have backpacks that exhibit a logo or other indicia of the particular group or institution with which they are affiliated. Other individuals may desire to show their support of a cause, an athletic team, a municipality, or other entity with which they wish to be identified. A backpack is particularly suited to this purpose because, when it is in use, it is nearly always exposed to the view of others, people tend to own few backpacks (i.e. many people own only one, replacing it when necessary) and backpacks are generally in public use almost daily.
Traditional backpacks have not fully satisfied the commercial potential of the product for a variety of reasons. One reason may be the economic difficulty of making many short production runs to meet the unique specifications of each of the many different schools, colleges, sororities, universities, teams, choirs, fraternal organizations, clubs, employers, and other affinity groups that may wish to provide its members with a recognizable visible link to one another. In addition to exhibiting indicia of affinity, a backpack can be used to exhibit advertising messages, logos, emblems, graphic fashion designs, slogans, business names, personal names, color schemes, and color coordination according to the wearer""s choice. If the color scheme is fixed (as it has traditionally been) when the backpack is presented to the prospective customer and offered for sale, an increasing number of options from which customers may select tends to increase product cost to offset the larger inventory, purchasing, and control costs of the manufacturer, the greater packaging, labeling, tracking and other costs of the distributor, and the increased inventory, stocking and training costs of the retailer. To further develop the market for this product, a method is needed by which the appearance of a backpack may be adapted to the specific preferences of various individuals and groups.
Since it appears unlikely that people will soon be persuaded to stop carrying backpacks by one strap, another way to reduce the likelihood of injury is to mitigate the deleterious effect that may be expected in some individuals by designing the backpack to accommodate the uses to which it will actually be put. In other words, none of the workers in the field have been able to create a backpack that is specifically adapted for being carried by one strap on one shoulder in addition to having the capability for being carried by two straps, one over each of a person""s shoulders.
There presently exists an unmet need for a backpack that a person can carry on one shoulder and that is adapted to minimize load imbalance. Another need is for a backpack that can be readily adjusted to properly fit the user. A third need is for a backpack that is adapted for being carried in different mannersxe2x80x94on one shoulder, on the other shoulder, on both shoulders, on one side, on the other side, higher, lower, etc.xe2x80x94to minimize the likelihood of muscle strain, other injury, and painful symptoms. Yet another unmet need exists in the art for a backpack adapted for carrying specific goods such as tools, clothing, materials, samples, or merchandise and which is readily adapted for being carried at the angles that, in terms of ergonomics, are the most appropriate carriage angles that can be obtained in practice whether the backpack is carried by a single strap, two straps, or with optional additional elements including, without limitation, waist bands, sternum straps, and/or shoulder harness.
A further unmet need in the field is for a backpack that can be readily adapted for the exhibition of various indicia and other graphic elements. Graphic elements can be displayed to great effect upon backpacks generally, but most particularly, from the straps. Various coordinating or contrasting colors and patterns may easily be incorporated into the ornamental appearance of the straps. Trademarks, certification marks, collective marks, and service marks can be applied under license from mark owners to provide enhanced appeal and sale of products including backpacks and backpack straps. Licensing of marks and designs has become an important source of revenue for many colleges and universities, for various supervisory organizations, and even for some commercial enterprises. Although commercial indicia, symbols of organizations, and other displays of affiliation or promotion by affixing the marks to articles such as backpacks, there has been little of such ornamentation applied. Use of backpacks to display affinity and commercial messages has been inhibited by the practical difficulty of producing at an economical price many customized versions of a relatively complicated product in order to meet the preferences of several unrelated niche markets.
What is needed, then, is a backpack that is easy to don and doff, that may be quickly and easily adjusted over an enhanced range of adjustment so that individuals of all sizes and body types can use an embodiment according to the present disclosure to mitigate the effects of carrying imbalanced loads including the load imbalances caused by carrying a backpack over one shoulder.
Further needs in the field include desirable appearance and ready adaptability to the needs of diverse individuals and groups each of which may have differing needs and purposes. Also sought in the field is a backpack with straps that may be quickly, easily, and economically removed from both the top and the bottom of the pack and replaced with straps that bear a different logo, a different color or a different color scheme.
All of the foregoing needs are sought in a backpack having straps that may be oriented diagonally or vertically, or otherwise, in order to achieve the most ergonomic configurations.
Considerable inventive skill has been applied by workers in the field of backpack design and fabrication to improve backpacks. Despite the sustained efforts of earlier inventors, advancements and refinements in backpack design continue in response to changing needs of those who use backpacks. The availability of new materials that may be incorporated into backpack construction, the evolving preferences of persons who use backpacks, changes in the composition of items that persons desire to carry in backpacks, and changes in fashion have contributed to activities and advances in advanced backpack styles. Those efforts have failed, until now, to produce a backpack having a range of adjustment sufficient to enable a backpack to be carried in relative comfort by one shoulder strap and to minimize the risk of muscle strain that might be caused by carrying unbalanced loads.
An embodiment according to the present disclosure is a backpack having removable, re-positionable carrying straps comprising a sack having a front portion, a back portion, a first side portion, a second side portion, a bottom, and a selectably closeable and openable top, a strap having a first end and a second end, a releasable fastener portion affixed proximate the first end of the strap, a releasable fastener portion affixed proximate the second end of the strap, a plurality of mating fastener portions affixed to the back of the sack and arranged with at least one mating fastener portion proximate the bottom of the sack and at least one mating fastener portion being affixed to the sack proximate the top, each of the mating fastener portions being adapted to selectably engage a releasable fastener portion.
The present invention is an improved backpack that may have two, or optionally, several, removable, re-positionable carrying straps. Both the upper and the lower ends of the carrying straps can be re-positioned laterally. Users may adjust strap lengths with conventional or subsequently developed means so that it fits a large range of body sizes and types. The adjustments also allow the pack to accommodate full pack loads, whether the weight is concentrated at the bottom, top, side, or distributed evenly.
The person using the new pack may carry it with one or both shoulders. It is an object of the invention to enable the pack to be better balanced than are conventional packs when it is being carried with one strap over one shoulder. Strap attachment and adjustment points can be established in a bilaterally symmetrical configuration so that an individual can shift the burden from one shoulder to the other regularly. It is desirable for a person to shift a load being carried from one shoulder to the other to reduce fatigue, stress, muscle strain, and joint wear. Although it accommodates being carried with one shoulder at a time, the new backpack is constructed so that it may, at any time, be carried on either shoulder or on both shoulders.
Functionality is enhanced because the wearer can balance the pack more evenly when carrying it on one shoulder; in addition, the pack straps are completely removable. A backpack user may find it more comfortable to remove the second strap when the pack is carried by a single strap. Removable pack straps make possible the option of providing a multiplicity of relatively inexpensive straps or strap pairs that may be attached interchangeably to the pack.
Straps adapted to a variety of purposes could be attached according to the user""s needs or wishes. By way of example, and not as a limitation, it is possible to make straps that match the colors of a school that the owner of the pack attends; straps may be colored and styled to coordinate with other items and apparel. Allowing a backpack purchaser to select straps that have a variety of colors and designs should make it easier for the person to coordinate the pack with wearing apparel to obtain the desired xe2x80x9clook.xe2x80x9d
The ability to replace backpack straps creates promotional and advertising possibilities that previously were simply unavailable. Straps may be emblazoned with advertising messages; straps may be given as premiums or promotional items at events; straps may be coated with reflective, luminescent, phosphorescent or safety materials; straps may coordinate with a particular marketing program or advertising participation campaign.
Specifically, the present disclosure teaches a method for displaying indicia comprising the steps of: making a backpack having removable, re-positionable carrying straps by, making a sack having a front portion, a back portion, a first side portion, a second side portion, a bottom, and a selectably closeable and openable top, affixing at least two first mating fastener portions proximate the bottom of the sack, each of the first mating fastener portions being adapted to selectably engage a first releasable fastener portion, affixing at least two second mating fastener portions proximate the top of the sack, each of the second mating fastener portions being adapted to selectably engage a second releasable fastener portion; making a plurality of carrying straps, each of which has a first end terminated by a first releasable fastener portion and a second end terminated by a second releasable fastener portion, applying indicia to the straps, and releasably attaching the straps to the backpack.
Backpack straps having various functional differences could be provided for different purposes. In order to reduce sway, for instance, straps that are stiffened to restrict lateral displacement may be provided to position the pack at a desired location or orientation for carrying. An example of material that could be incorporated into a backpack strap to prevent lateral displacement is any of a variety of linked belts or roller chains of the type commonly used on bicycles. Roller chains are available in duplex, triplex, and higher multiple configurations in addition to the familiar simplex bicycle chain. Functionally similar for the purposes of this disclosure are various linked belts which act as a series of hinges. Pivoting movement in one plane is nearly effortless while movement perpendicular to that plane is restricted. Some other materials have similar properties. For example, it may be possible to find or create a polymer, or blend of polymers that could be incorporated within backpack straps to obtain properties useful in holding the backpack in the most ergonomically favorable position that is practical for the wearer.
It may also be desirable to include semi-rigid stiffener members within, in addition to, or in place of straps. Such members may provide useful assistance in holding the pack at desired locations or orientations and they could be conformable to the body of each individual.
In order to maximize the functionality available to a person using the present invention, the new backpack may optionally be fitted with a handle for hand-carrying the pack. An alternative configuration may optionally include either an optional long strap or else means for interconnecting the two over-the- shoulder straps so that the embodiment may be carried as a shoulder bag.
The backpack described generally, above, and in detail, below, making specific reference to the various drawing figures, overcomes several of the limitations inherent in backpacks known in the art previously and minimizes the impact of other limitations.